Electric switch



July 8, 194L A. w. KRIEGER 2,248,362

ELECTRIC SWITCH Filed Nov. 16, 1940 3 Sheets-Sheet 1 'au `1 ze@ July 8, 1941. A. w. KRn-:GER

ELECTRIC SWITCH Filed Nov. 1e, 1940 3 sheets-sheet 2 July 8, 1941. A, w KRlEGER 2,248,362

ELECTRIC SWITCH Filed NOV. 16, 1940 5 Sheets-Sheet 3 Patented July 8, 1941 ELECTRIC SWITCH Alvin W. Krieger, Milwaukee, Wis., assigner to Cutler-Hammer, Inc., Milwaukee, Wis., a corporationoi' Delaware Application November 16, 1940, Serial No. 365,907

13 Claims.

This invention relates to improvements in electric switches, and the invention relates more particularly to three-pole, alternating current controlling switches of the toggle lever operated type.

A primary object of the invention is to generally improve and simplify the details of construction and assembly of the parts and the operating characteristics of such switches.

Another object is to provide improved means for insulating the contact and terminal members of the respective poles of the switch, whereby the current controlling capacity of the latter is increased.

Another object is to provide insulating arcing chambers for the sets of contacts forming the respective poles of the switch.

Another object is to provide improved and simplied means for effecting like operations of the contactors jointly.

Another object is to provide a switch base of molded insulating material adapted to accommodate various different forms of terminal members which may be so arranged as to facilitate attachment of circuit wires thereto.

Another object is to provide novel forms of superstructure for association with other parts of the switch, to provide for one-hole mounting of multiple-screw mounting of the latter.

Other objects and advantages of the invention will hereinafter appear.

The accompanying drawings illustrate certain embodiments of the invention which will now be described, it being understood that the embodiments illustrated are susceptible of modification in respect of certain structural details thereof without departing from the scope of the appended claims.

In the drawings,

Figure 1 is a longitudinal, vertical sectional View (double-scale) of a three-pole, double-throw switch constructed in accordance with my invention,-the section being taken on the line i-l of Fig. 2.

Fig. 2 is a vertical sectional viewl on the line 2 2 of Fig. 1.

Fig. 3 is a bottom plan view (actual size) of the switch shown in Figs. 1 and 2.

Fig. 4 is a top plan view of the molded insulating base of the switch, with the contacter fulcrums, the stationary contacts, and one of the contactors in position.

Fig. 5 is a fragmentary sectional view showing a special form of contactor,-three of which will be employed when it is desired to produce a (Cl. 20o- 6) lll three-pole, double-throw switch without an olf position.

Fig. 6 is a top plan view of the switch shown in Figs. 1 to 4, illustrating the manner in which the same is adapted for two-screw mounting within a casing. upon a panel, or upon any other suitable support.

Fig. 7 is a transverse vertical sectional view of a three-pole, double-throw, alternating current controlling switch, having wiring terminals of the solder-lug type, and means to provide for onehole mounting of the switch,the section being taken on the line l--l of Fig. 8.

Fig. 8 is a. vertical sectional view, on the line 8-8 of Fig. '1.

Fig. 9 is a top plan view of a modied form of molded insulating base adapted to be used in constructing a three-pole, single-throw switch,- the contacter supports, the contacts and one oi the three contactors being shown in position.

Fig. 10 is a view, partly in side elevation and partly in vertical section, of the assembled parts of a switch oi the type shown in Fig. 9, and provided with means to adapt the same for onehole mounting.

Fig. 11 is a bottom plan view of a switch like that shown in Figs. 9 and 10,-the eyelets for securing the top plate being omitted.

Fig. 12 is a fragmentary view, partly in vertical section and partly in side elevation, of a switch similar to that shown in Fig. 10,--but provided with means to adapt the same for two screw mounting, and further provided with spring means to form a switch of the momentary contact type.

Fig. 13 is a sectional view, on the line I3-II of Fig. 12, illustrating the return spring for the switch lever, and illustrating the formation of the top plate to provide for support oi the pivot pin, and

Fig. 14 is a sectional view of a portion of the insulating base, illustrating the special form of the contactors which would preferably be employed in a switch like that of Fig. 12, if the return spring of the latter switch were omitted.

Referring first to Figs. 1 to 4 of the drawings. the numeral I5 designates a base molded from a suitable insulating material,preferably Bakelite 'I'he main body portion of-base il is preferably of substantially rectangular or boxlike contour, and the same is provided with an upwardly opening substantially rectangular recess I6. Recess I6 is divided into three longitudinally extending compartments Il, I8 and I9 of equal size by a pair of barriers or walls 20 and 2| formed integrally with the bottom and end walls of said recess. The upper edges of barriers 20 and 2| are arcuately depressed or cut away, as shown at 202 and 2|a to provide clearance for oscillatory movement of an insulating operating element of the switch, as hereinafter more fully described.

Each of the compartments to |9 is provided in its bottom wall with a pair of openings, located adjacent to the respective ends thereof, to accommodate the Shanks of a pair of rivets 22 the heads 22a of which form the stationary contacts of the switch. Rivets 22 are preferably formed of fine silver, or of a similar metal having good electrical conductivity and low contact resistance. The shanks of rivets 22 penetrate alined openings in a corresponding number of wiring terminal plates 23 and have their ends upset over said terminal plates, as shown in Figs. l and 3, to secure the latter to base I5. Terminal plates 23 are positioned atwise upon the bottom surface of base I5, and said plates are tapped to receive the upwardly extending Shanks of binding screws 24 of well known form-said Shanks being positioned exteriorly of the respective end walls of the base recess I6, as best illustrated in Fig. 1.

In practice I prefer to position beneath the head 2211 of each contact a metal washer 26. Washers 26 perform several desirable functions; namely, they afford proper spacing of the contact heads 22EL upwardly from the bottom wall of the recess I6; they act to dissipate heat generated at the contacts as an incident to arcing; and they serve to reinforce the bottom wall of recess I6 during the operation of upsetting the shanks of rivets 22 over plates 23.

Each compartment Il to I9 is provided at the midpoint of its bottom wall with a third opening to accommodate the shank of a. rivet 21, which is preferably formed of brass, or a similar base metal of good conducting quality. Surrounding each of the last mentioned openings in the bottom walls of said compartments is a rectangular countersink or depression, such as shown at I8a in Fig. 1; which countersinks accommodate the at connecting portions of three substantially U-shaped members 28, whereby rotation of said members is prevented when the same are attached to base I by said rivets 2l. The shanks of rivets 21 are upset over the flat portions of a corresponding number of terminal members secured to the lower surface of base |5,-the two end terminal members 29, 29 being of like form, in respect of the (oppositely arranged) portions 292, 29a which extend downwardly at right angles to their respective at portions, and being adapted to accommodate the shanks of binding screws 24, the Shanks of which extend toward each other. The intermediate terminal member 3U (Fig. 2) has ite terminal screw receiving portion 3l)a extending downwardly from the flat portion thereof at less than a right angle, to permit access to its associated binding screw without interference from the shank of the adjacent (left-hand, Fig. 2) terminal screw and portion 25N.

As shown in Figs. 1 and 2, and particularly in Fig. 3, the bottom surface of base |5 is provided with integral barrier portions forming walls surrounding the at portions of each of the nine terminal members on at least three sides,-the flat portion of the intermediate or central terminal member 30 being surrounded on all four sides by the barrier walls. The advantages of this arrangement will be apparent to those skilled in the art.

Base I5 is provided at opposite ends thereof with alined integral projections l5a and |51, of substantially rectangular contour, which extend throughout the entire depth of said base. Said projections are respectively provided with recesses |5c and l5d which open to the bottom surface of base I5 and to the opposite ends of the latter. Said projections are provided with openings I5e and |5f to accommodate the shanks of elements adapted to secure the metal top plate 3| to base I5. As shown in Fig. l, the securing elements preferably comprise a pair of eyelets 32 the heads of which engage the top plate and the shank ends of which are upset over the upper end walls of recesses I5c and 15d. As will be noted, the recesses I5c and l5d provide clearance for the shanks of the intermediate binding screws 24 at opposite ends of base I5. Likewise, as illustrated in Figs. l and 3, the opposite side walls of recesses I5c and I5d serve to provide efficient insulating barriers between said intermediate terminals at the base ends and the respective end terminals at opposite sides of said intermediate terminals.

As shown in Figs. 1 and 6, the top plate 3| is of a shape and size to correspond with and completely cover the upper surface of base |5. Plate 3| is provided with a bulge or projection 3| of elongated rectangular contour extending transversely across the base (see Fig. 6). Projection 3|a is provided at its upper end with a substantially flat surface portion 3|b (Figs. 1 and 2), the major portion of which is punched out or cut away to provide the opening 3|C (see also Fig. 13). However, integral portions of projection 3|a at opposite ends of the opening 3|C are bent or formed to extend downwardly at substantially right angles to the surface portion 3|, and then toward each other in the form of upwardly opening channels or bearings 3|d and 3|e for the opposite ends of a pivot pin 32". As best illustrated in Figs. 2 and 13, the arrangement is such that substantial endwise displacement of pin 32x is prevented.

Pin 32X is adapted to freely penetrate an opening 33 provided at an intermediate point in the length of a fiat, punched sheet metal actuating lever 33. In practice the upper end of lever 33 is provided with a projection or tongue (not shown) of reduced width which is adapted to be received with a drive t within a suitable recess in a ball or knob 34, which is preferably formed of aluminum. The lower end of lever 33 is provided with a centrally located substantially rectangular notch 33h, thus providing a fork which is adapted to straddle the upper end of a molded insulating block 35 for driving of the latter. Block 35 is in general of approximately rectangular contour and is of a length to extend transversely across the major portion of the width of recess I 6, but with clearance to provide for oscillatory movement of the former, as shown in Figs. 2 and 7. As best illustrated at 35a and 35b in Fig. '7, the opposite ends of block 35 are preferably of convex or semicylindrical contour in horizontal cross section.

Block 35 is provided at opposite sides thereof with pairs of integral spaced lugs or projections 35c and 35d which accommodate the forked lower end of lever 33 to prevent substantial lateral displacement of said parts relatively to each other and to insure against tilting of said block relatively to said lever.

Block 35 is provided with three substantially cylindrical recesses 35, 35f. and 35' which open to the lower surface thereof at laterally spaced points corresponding to the spacing of the longitudinally alined sets of stationary contact tips 22*l and U-shaped members 28. Block 35 is provided on opposite sides of each recess 35e, 35t and 35lz with pairs of integral parallel fillets or projections 35h which, as shown in Fig. 1, act to increase the effective depth of said recesses. Telescopically tting into each of the recesses 35e, 35t and 351 is a hollow, substantially cylindrical insulating member 36 having a hemispherical lower end; each of the members 36 lbeing biased outwardly by a coiled compression spring 4|.

Each of the U-shaped members 28 is provided in its parallel side portions with approximately rectangular upwardly opening notches (see Figs. 1 and 4) to accommodate the arms 31 and 31b of a correspondingy number of bridging contactors 31. As shown in Figs. 1, 2 and 4 each oi.' the contactors 31 has a relatively wider central portion which is bent to arcuate form to-provide for positive positioning of the lower end of one of the members 38 therewithn in the central or intermediate position of lever 33,-the extra width of said central portion of each contactor providing lugs which are positioned between the aforementioned side portions of each member 28 to insure maintenance of the ycontactors in assembled relation to the respective members 28.

As shown in Fig, l, the arms 31* and 31h of contactors 31 are angled upwardly to a predetermined degree relatively to each other, and the free ends 31 and 31d of said arms are oiliset downwardly in planes at slight angles thereto respectively. The arrangement is such that said free ends 31c and 31d are located in planes radial to the fulcrum points of the respective arms upon the members 28. The arrangement is further such that the intermediate portions of the active arms ill'a or 31h will be angled upwardly slightly, with respect to the horizontal in the respective on positions of the switch. However, because of the illustrated relationship of the pivot 32x of lever 33 and the active fulcrums of the several contactors the aforementioned upward angle of the arms engaged by members 36 in each on" position will not provide for return of the contactors to their intermediate ofi position, except upon manual operation of the lever 33. Each contactor 31 has attached to its free end portion (as by spotwelding) a contact tip 31e of fine silver or the like for cooperation with the respective tips or contact heads 22 aforementioned.

Securedl to the ilat portion 3|b of top plate 3i i as by spot-welding at the points 38, 38b,' Figs. 2 and 6) is a substantially square, at sheet metal plate 38 of smaller size than said top plate. Plate 38 is provided with a slot 38c to provide clearance for lever 33 during oscillatory movement of the latter and to restrict the same to oscillatory movement in a single plane. Plate 38 is provided with a pair of alined tapped openi ings 38d and 38e to accommodate the shanks of a pair of screws (not shown whereby the switch as a whole may be attached to a casing, panel or the like. Plate 38 is also preferably provided when initially formed with openings 38, 38B, 38h and 38l adjacent to each of the four corners thereof, which openings may be alternatively or additionally tapped to provide for attachment thereof to a 'panel or other suitable support. A

As shown in Figs. l, 2 and 6, plate 38 is sheared or cut along parallel lines at two points, and the material between the respective pairs of shear lines is bent downwardly or deformed to provide the portions 381 and 38k which are adapted to engage and retain the pivot pin 321x within its bearings 3|d and 3| aforementioned.

The switch aforedescribed has a rated capacity for control of alternating current as follows: 10 amperes at 250 volts; one-half horsepower, single phase, volts; three-fourths horsepower, single phase, 220 to 550 volts; and three-fourths horsepower, 2 and 3 phase, 110 to 550 volts.

In the modiiied form of my invention shown in Fig. 5 most of the parts of a three-pole, double-throw switch may be identical with the parts aforedescribed, and the like parts illustrated in Fig. 5 have been given corresponding numerals of reference. In Fig. 5 the purpose is to provide a three-pole, double-throw switch without an off position. Accordingly I have shown in Fig. 5 a special form of contactor 39 which is bent or formed to provide at its mid-length a ridge or apex 39, from which the respective arms of the contactor slope or curve downwardly to a slight degree and then upwardly to a corresponding degree to provide the arcuate portions. 'I'he free end portions 33d and 38 of the contactor extend in a straight line from the respective portions 39b and 38, whereby the active free end portion will be located in a plane parallel to the bottom wall Iii of the base recess in the respective on position of the switch.

The fulcrum means for each contactor 33 comprises a U shaped member 40 whose upstauding arms are arranged in parallel planes extending longitudinally of the contactenone of said arms being shown at 40"; and each of the arms is provided with an upwardly opening rectangular not-ch, as shown at 40h. The contactor is provided at its mid-length with a pair of laterally extending lugs, one oi which is shown at 33f. The opposite edges of the pairs of lugs 39f are alternately engageable with the straight lower walls of the notches 48h to provide different fulcrum points for the contactors in the respective "or-i positions of the switch. In the usual or normal operation of such a switch the contactors will not be moved out of a given on position without simultaneously being moved to their other on position. Also the arrangement'is such that upon release of the manual operating lever (such as 33 of Figs. 1 to 4 and 6) the contactors of Fig. 5 will be jointly moved automatically to one or the other of their on positions.

The switch illustrated in Figs. 'l' and 8 is adapted to perform the same functions as that of Figs. 1 to 4 and 6,-and many of the switch parts may be identical with those aforedescribed, such parts having been given corresponding numerals of reference. The switch of Figs. 'I and il` however, is provided with parts to adapt the sa me to one-hole mounting. Although the switch of Figs. 'I and 8 is provided with nine solder-type wiring terminals I2, it is to be understood that either of the two forms of wiring terminals may be employed in either of forms of switches thus far referred to.

The top plate 43 in Figs. 7 and 8 is provided with a bulge or projection 43 of elongated rectangular contour, the long sides 43", 43b of which (Fig. 8) are arranged at angles diverging down-` wardly with respect to eachother to provide proper clearance for the oscillatory operating lever 44. 'I'he flat upper end 43c of said projection is perforated to accommodate the reduced lower end of a hollow, externally threaded bushing 45,-said lower end being upset over the inner surface of said flat portion of the top plate to rigidly secure said parts to each other.

As will be noted, the point of pivotal support of lever 44 is farther removed from the contactors than is the pivot 32x of Figs. 1 to 4. Thus, in Figs. 7 and 8, a headed pin 46 extends diametrically across bushing 45 through alined countersunk openings in the latter,-said pin having its shank end upset to secure the same permanently and non-rotatably to the bushing. A tubular member 41, of substantially less length than the inside diameter of the bushing is rotatably tted within an opening 44B in lever 44, and member 41 is in turn rotatably supported by pin 46. The upper (initially closed) end of bushing 45 is provided with a kerf 45*1 to accommodate the end of lever 44 which is inserted upwardly therethrough, the walls of said kerf acting to limit lever 44 to oscillatory movement in a single plane. Lever 44 has a ball or knob 48 attached thereto, with a drive fit as aforedescribed, after upward insertion of the lever through said kerfed end of the bushing.

The lever end 44b of lever 44 ls forked to cooperatively engage block 35, as described in connection with Figs. 1 to 4. The contactors 49 employed in Figs. 7 and 8 are slightly different in form from those of Figs. 1 to 4,-the same each comprising a downwardly curved intermediate portion 49a having laterally extending lugs (one of which is shown at 49b in Fig. 8) for retention thereof in assembled relation to members 28. The arms 49C and 49d of each contactor extend in a straight line from each of the respective fulcrum points of the contactor,-sad arms being arranged at a predetermined angle to each other. The arrangement is such that in each on position of the switch one of the arms 48C or 48d will be located in a plane substantially parallel to the bottom wall of base recess I6; said arms being provided with silver contact tips 49e like the tips 3lE of Figs. 1 to 4. Inasmuch as the insulating base I is identical with that aforedescribed, the three compartments formed by the integral walls or barriers will act to provide arcing chambers for the respective sets of contacts and contactors. Bushing preferably has a pair of nuts 50 and 5l (Fig. 8) associated therewith to provide for adjustable mounting thereof within a single opening in a casing or panel of any usual or desired thickness. Bushing 45 is also preferably provided with a vertical groove 45b (Fig. 8) to accommodate a positioning tongue of a plate (not shown) having legends thereon to indicate the respective on positions and the off position of the switch mechanism. In practice base I5 is preferably provided upon the opposed side walls of recess I6 (see Figs. 4 and 8) with slight inward extensions ISK and l5h having flat surfaces for cooperation with the ends of block 35 to prevent substantial lateral displacement thereof in either direction. As shown in Fig. 8, lever 44 engages bushing 45 either (or both) above and below the point of pivotal support to limit the degree of oscillatory,

movement thereof in each direction.

Figs. 9, 10 and 1l illustrate a three-pole, single throw on and ol switch constructed in accordance with my invention. The molded insulating base 52 is of substantially the same size and external contour as the base l5 aforedescribed. Integral barriers 52n and 52b like those aforedescribed provide for formation of three compartments or arcing chambers 52C, 52d and 52e, the bottom walls of which are left dat or smooth, and each of said bottom walls is provided with a pair of openings which are spaced and located in a manner corresponding to that of the end openings of the compartments in the switches of Figs. 1 to 8. Silver rivets 22 like those aforedescribed have their Shanks penetrating the openings at corresponding ends of the respective compartments whereby the heads 22a are adapted to form the stationary contacts of the switch; said heads 22a overlying the metal washers 26 which perform the various functions aforementioned in the description of Figs. 1 to 4. The shanks of rivets 22 penetrate openings provided in the terminal members 53 and are upset over the latter, as shown in Figs. 10 and 11 to secure said parts to base 52. Although I have shown the perforated free end portions of terminal members 53 bent downwardly to provide for looping and soldering of the circuit wires thereto, it is to be understood that said members 5E may be left in a straight or flat condition (as blanked) if it is desired to reduce the overall depth of the switch. Similarly, it is to be understood that binding screw wiring terminals (such as the end terminal members 23 of Figs. 1 to 4) may be employed in the switch of Figs. 9 to 11, if desired.

Each compartment 52C, 52d and 52e of the recess in base 52 has positioned therein a fulcrum member comprising a flat portion 54 and a notched portion 54a bent upwardly at a right angle thereto,each of said notched portions being adapted to receive and retain against endwise displacement the complementally notched intermediate portion 55a of a corresponding number of bridging contactors 55, as shown in Figs. 9 and 10. As shown in Fig. 10, each contactor 55 has its arm 55b arranged to lie in a plane substantially parallel to the bottom wall of its respective compartment in the on position of the switch,-each arm 55b having a silver tip 55c attached thereto for cooperation with one of the stationary contacts 22a. The other arm 55d of each contactor has its free end 55e bent downwardly at substantially a right angle thereto to abut against the flat portion 54 of the fulcrum member in the off position of the switch,- the arrangement being such that the main body portion of arm 55d will then be located in a plane substantially parallel to the bottom wall of the compartment.

Each of the fulcrum members 54 is rigidly attached to base 52 as by means of a. rivet 56 of brass or other good conducting materiaL-the hollow end of each of said rivets being upset over the fiat portions of terminal members 53 like those aforedescribed.

As best illustrated in Fig. 11, base 52 is provided on its lower surface with integral barrier portions 52f, 528, 52h and 52i to properly insulate the various wiring terminal members 53 from each other.

The modified form of three-pole, single throw switches shown in Figs. l2 and 13 comprises a combination of the insulating base 52, and its associated contact and terminal members, such as shown in Figs. 9 to 11, with the operating mechanism or superstructure for a switch of the screw-mounting type, such as shown in Figs. l

to 4 and 6,-like parts afore-described having been given like numerals of reference. In Figs. l2 and 13, however, the switch is of the momentary contact type. )That is to say, the switch is normally-biased to its off position as by means of a single torsion spring 51, which has its two straight end portions 51'l and 51b accommodated in and retained by suitable grooves 3|t and Ill formed in the flat upper surface 3 lb of projection 3i. Arms 51a and 51b extend downwardly to and merge with theA respective coiled portions 51c and 5'1d which surround pin 32* on opposite sides of lever 33,--said coiled portions terminating in a U-shaped connecting portion 51 which is positioned withinfa notch 33 provided in that side of lever 33 opposite to the spring ends 51Il and 51h. As shown in Fig. 12, spring 51 serves to automatically return the switch contactors to circuit-interrupting position upon manual release of lever 33. As will be apparent to those skilled in the art the switch of Figs. 12 and 13 might be alternatively constructed (by use of the same switch parts) to provide for momentary on positioning of the switch parts and for automatic return thereof to on position upon manual release of lever 33. Such alternative arrangement would merely involve a reversal of the relative points of attachment and positioning of the stationary and movable contact elements with respect to each compartment. Thus, in Fig. l2, the stationary contacts 22 would be located at the left-hand ends of the respective compartments, and the members 54 would be located at the right-hand ends of said compartments, with a consequent reversal of the positions of the bridging contactors 55.

Fig. 14 illustrates the preferred form in which the bridging contactors 58 of the switch would be made, if the return spring 51 of Figs. 12 and 13 were omitted. Thus the portion 5tl of the contactor arm would be angled downwardly to a slight degree out of parallel relation to the bottom wall of the respective compartment in the on position of the switch, and the end portion 58C of the arm portion 58b would be bent downwardly at substantially less than a right angle with respect to the latter, so that arm portion 58b would likewise be angled downwardly to a slight degree out of parallel relation to the bottom wall of the respective compartment in the off position of the switch. The arrangement illustrated in Fig. 14 has the advantage of providing a more definite and positive feel, to indicate to the operator that the switch has been moved to either its on or its oi position. As will be noted, the arm portion 58d is arranged to lie in a plane substantially parallel -to the bottom wall of the compartment in the on position of the switch,said portion having a silver contact tip 59 welded or otherwise rigidly secured thereto for cooperation with one of the stationary contact tips 22.

l. In a multi-pole electric switch adapted for control oi' alternating current circuits, in combination, a molded insulating base of substantially rectangular contour adapted to be produced by a straight-line .molding operation, said base having a relatively deep substantially rectangular recess formed therein and opening to the upper surface thereof, said base having at least one in sulating barrier formed integrally with the bottom and end walls o1 said recess, the end portions of said barrier being'of a height substantially coprovide a pair of substantially separate arcing compartments, a stationary contact located in each of said compartments adjacent to one end o1' the latter, a bridging contactor supported within an open pivotal bearing in each of said compartments in predetermined spaced relation to the respective stationary contacts, means for eiiecting like operation of said contactors jointly into and out of bridging relation to the respective stationary contacts, said last mentioned means including an oscillatory insulating block and spring-pressed elements carried thereby for cooperative engagement with the respective contactors, the intermediate portion of said barrier being shaped to provide for clearance between the same and at least a portion of said block during oscillatory movement of the latter within said recess, and wiring terminal members respectively associated with each of said contacts and said contactors, said last mentioned members being exposed upon the lower surface of said base.

2. In a multi-pole electric switch adapted for control of alternating current circuits, in combination, a molded insulating base of substantially rectangular contour adapted to be produced by a straight-line molding operation, said base having a relatively deep substantially rectangular recess formed therein and opening to the upper surface thereof, said base having at least one insulating barrier formed integrally with the bottom and end walls of said recess, the end portions of said barrier being of a height substantially coextenslve with the height of said recess to thereby provide a pair of substantially separate arcing compartments, a stationary contact located in each of said compartments adjacent to one end `of the latter, a bridging contactor supported within an open pivotal bearing in each of said compartments in predetermined spaced relation to the respective stationary contacts, means for effecting like operation of said contactors jointly into and out of bridging relation to the respective stationary contacts, said last mentioned means including an oscillatory insulating block and spring-pressed insulating elements carried thereby for cooperative engagement with the respective contactors, the intermediate portion of said barrier being shaped to provide for clearance between the same and at least a portion of said block during oscillatory movement of the latter Within said recess, wiring terminal members respectively associated with each of said contacts and said contactors, said last mentioned members being exposed upon the lower surface of said base, and said lower surface of the base having insulating barriers formed integrally therewith and interposed between the adjacent wiring terminal members.

3. In a three-pole, double-throw electric switch adapted for control of alternating current circuits, in combinaton, a molded insulating base of substantially rectangular contour adapted to be produced by a straight-line molding operation, said base having a relatively deep substantially rectangular recess formed therein and opening to the upper surface thereof, said base having a pair of insulating barriers formed integrally with the bottom and end walls of said recess, the

end portions of said barriers being of a height substantially coextensive with the height of said recess to thereby provide three substantially separate arcing compartments, a pair of stationary contacts located in each of said compartments adjacent to the respective ends of the latter, three extensive with theheight of said recess to thereby bridging COIllaCtOrS SuplJUrted Within Open Divotal bearings in the respective compartments in equally spaced relation to the contacts of the respective pairs, means for effecting like operation of said contactors jointly into and out of engagement with corresponding contacts of said pairs, said last mentioned means includlnlg'an oscillatory block' of molded insulating'matrial and spring-pressed molded insulating plungers carried thereby for cooperative engagement with the respective contactors, the intermediate portions of the respective barriers being arcuately depressed to provide for clearance between the same and said block during oscillatory movement of the latter within said recess, and nine wiring terminal members respectively associated with each of said contacts and said contactors, said last mentioned members being exposed and readily accessible for wiring at the lower surface of said base.

4. In a three-pole, double-throw electric switch adapted for control of alternating current circuits, in combination, a molded insulating base of substantially rectangular contour adapted to be produced by a. straight-line molding operation, said base having a relatively deep substantially rectangular recess formed thereinand opening to the upper surface thereof, said base having a pair of insulating barriers formed integrally with the bottom and end walls of said recess, the end portions of said barriers being of a height substantially coextensive with the height of said recess to thereby provide three substantially separate arcing compartments, a pair of stationary contacts located in each of said compartments adjacent to the respective ends of the latter, three bridging contactors supported within open pivotal bearings in the respective compartments in equally spaced relation to the contacts of the respective pairs, means for effecting like operation of said contactors jointly into and out of engagement with corresponding contacts of said pairs, said last mentioned means including an oscillatory block of molded insulating material and spring-pressed molded insulating plungers carried thereby for cooperative engagement with the respective contactors, the intermediate portions of the respective barriers being arcuately depressed to provide for clearance between the same and said block during oscillatory movement of the latter within said recess, nine wiring' terminal members respectively associated with each of said contacts and said contactors, said last mentioned members being exposed and readily accessible for wiring at the lower surface of said base, and said lower surface of the base having insulating barriers formed integrally therewith and interposed between all of the adjacent wiring terminal members.

5. In a three-pole, double-throw electric switch adapted for control of alternating current circuits, in combination, a molded insulating base of substantially rectangular contour adapted to be produced by a straight-line molding operation, said base having a relatively deep substantially rectangular recess formed therein and opening to the upper surface thereof, said base having a pair of insulating barriers formed integrally with the bottom and end walls of said recess, the end portions of said barriers being of a height substantially coextensive with the height of said recess to thereby provide three substantially separate arcing compartments, a pair of stationary contacts located in each of said compartments adjacent to the respective ends of the latter, three bridging contactors supported within open piv- Cil otal bearings in the respective compartments in equally spaced relation to the contacts of the respective pairs, means for effecting like operation of said contactors jointly into and out of engagement with corresponding contacts of said pairs, said last mentioned means including an oscillary block of molded insulating. material and spring-pressed molded insulating plungers car ried thereby for cooperative engagement with the respective contactors, the intermediate portions of the respective barriers being 4arcuately depressed to provide for clearance between the same and said block during oscillatory movement of the latter within said recess, nine wiring terminal members respectively associated with each of said contacts and said contactors, said last mentioned members being exposed and readily accessible for wiring at the lower surface of said base, and said lower surface of the base having insulating barriers formed integrally therewith and interposed between all of the adjacent wiring terminal members, the centrally located terminal being surrounded on all sides thereof by certain of said insulating barriers.

6. In an electric switch of the character de scribed, in combination, a molded insulating base having a recess formed therein and opening to the upper surface thereof, a plurality of laterally spaced contacts located within said recess, a corresponding number of contactors pivotally supported in said recess in overlying relation to the respective contacts and tiltably movable into and out of bridging engagement with the latter, means for effecting such movements of said contactors jointly, said means comprising a molded insulating block oscillatable within said recess, a plurality of spring-pressed insulating plungers carried by said block for continuous engagement with the respective contactors, a forked metal lever having a loose, telescopic' interlocking engagement with said block for effecting oscillatory movement of the latter, a metal top plate having an upwardly extending hollow projection, said projection having a pair of lugs formed integrally therewith and oii'set downwardly from the upper surface thereof to provide a pair of alined upwardly opening pivot bearings, said lever having an opening formed therein, a pin of circular cross section freely penetrating said lever opening and having its ends seated within said pair of pivot bearings, a metal support plate superimposed upon the upper surface of said top plate projection and rigidly and permanently secured to the latter, said support plate overlying said pin to restrain the latter against displacement; from said bearings, said support plate having a slot formed therein to accommodate said lever and to substantially limit the latter to oscillatory movement in a single plane, and said support plate also having a plurality of openings formed therein to provide for removable attachment of the switch unit in a substantially flush relation to a panel or the like.

7. In an electric switch of the character described, in combination, a punched and stamped sheet metal top plate of greater length than width, said plate having an upwardly extending hollow projection of elongated substantially rectangular contour occupying the major portion of the width of said plate at the mid-portion of its length, said projection having a pair of lugs formed integrally with opposite ends of its top surface and bent downwardly and then inwardly toward each other` the inwardly bent portions of said lugs being formed to provide upwardly g 2,949,345: opening bearings, a fiat, punched sheet metal actuating lever having a circular opening formed therein, a pin of circular form in transverse cre s section freely insertable through said lever opening and having its ends seated in said bearings, a substantially flat, punched sheet metal support plate of a width approximately correspending to the length of said projection, said support plate being spot-welded to said projection at points adjacent to the respective lugs,

said support plate being sheared along parallel pairs of lines to deilne areas overlying the respective end portions of said pin, and the material of said areas being depressed to provide portions offset downwardly into engagement with the end portions of said pin, whereby the latter is positively restrained against upward displacement from said bearings.

8. In an electric switch of the character described, in combination, a punched and stamped sheet metal top plate of greater length than width, said plate having an upwardly extending hollow projection of elongated substantially rectangular contour occupying the major portion of the width of said plate at the mid-portion of its length, said projection having a pair of lugs formed integrally with opposite ends of its top surface and bent downwardly and then inwardly toward each other, the inwardly bent portions of said lugs being formed to provide upwardly opening bearings, a ilat, punched sheet metal actuating lever having a circular opening formed therein, a pin of circular form in transverse cross section freely insertable through said lever opening and having its ends seated in said bearings,

' a substantially at, punched sheet metal support plate of a width approximately corresponding to the length of said projection, said support plate being spot-welded to said projection at points adjacent to the respective lugs, said support plate being sheared along parallel pairs of lines to define areas overlying the respective end portions of said pin, the material of said areas being depressed to provide portions offset downwardly into engagement with the end portions of said pin, whereby the latter is positively restrained against upward displacement from said bearings, and said support plate having a relatively narrow slot formed therein to accommodate the upper end portion of said lever during oscillatory movement thereof and to substaritially limit the same to oscillatory movement in a single plane.

9. In an electric switch of the character described, in combination, a. punched and stamped sheet metal top plate of greater length than width, said plate having an upwardly extending hollow projection of elongated substantially rectangular contour occupying the major portion of the width of said plate at the mideportion of its length, said projection having a pair of lugs formed integrally with opposite ends of its top surface and bent downwardly and then inwardly toward each other, the -inwardly bent portions of said lugs being formed to provide upwardly opening bearings, a iiat, punched sheet metal actuating lever having a circular opening formed therein, a pin of circular form in transverse cross section freely insertable through said lever opening and having its ends seated in said bearings, a substantially flat, punched sheet metal support plate of a width approximately corresponding to the length of said projection, said support plate being spot-welded to said projection at points adjacent to the respective lugs, said support plate being sheared along parallel pairs ot lines to define areas overlying the respective end portions of said pin, the material of said areas being depressed to provide portions offset downwardly into engagement with the end portions of said pin, whereby the latter is positively restrained against upward displacement from said bearings, said support plate having a relatively narrow slot formed therein to accommodate the upper end portion of said lever during oscillatory movement thereof and to substantially limit the same to oscillatory movement in a single plane, and said lever having a forked lower end to provide for free movement thereof into interlocking and driving engagement with an insulating operating element of suitable form.

10. In anelectric switch of the character described, in combination, a punched and stamped sheet metal top plate of greater length than width, said plate having an upwardly extending hollow projection of elongated substantially rectangular contour occupying the major portion of the width of said plate at the mid-portion of its length, said projection having a pair of lugs formed integrally with opposite ends of its top surface and bent downwardly and then inwardly toward each other, the inwardly bent portions of said lugs being formed to provide upwardly opening bearings, a flat, punched sheet metal actuating lever having a circular opening formed therein, a pin of circular form in transverse cross section freely insertable through said lever opening and having its ends seated in said bearings,

a substantially flat, punched sheet metal support plate of a width approximately corresponding to the length of said projection, said support plate being spot-welded to said projection at points adjacent to the respective lugs, said support plate being sheared along parallel pairs of lines to define areas overlying the respective end portions of said pin, the material of said areas being depressed to provide portions oil'set downwardly into engagement with the end portions of said pin, whereby the latter is positively restrained against upward displacement from saidbearings, said lever having a portion of reduced width at its upper end, and a metal knob of approximately spherical form, said knob having a recess formed therein to accommodate with a drive ilt the upper end portion of said lever.

11. In an electric switch of the character described, in combination, a recessed molded insulating base, a punched and stamped sheet metal top plate rigidly attached to said base and overlying said recess, a fiat, punched sheet metal actuating lever, means carried by said top plate to provide for pivotal support of said lever, said lever having a substantially rectangular notch opening to the lower end thereof, a molded insulating Vblock adapted to be produced by a straight-line molding operation, said block having an upper end portion adapted to fit freely but closely within the walls of said notch to provide for oscillatory movement of said block with said lever, said block having grooves formed thereon for cooperation with the material of said lever on opposite sides of said notch, whereby lateral displacement of said lever and said block relatively to each other is substantially prevented, said block having a plurality of recesses formed therein and opening downwardly with respect thereto, a spring-pressed insulating plunger located within each of said recesses, and a corresponding number of tiltable contactors located ltacts respectively associated therewith, said last mentioned means comprising a molded insulating block having a plurality of spring-pressed plungers associated therewith for continuous engagement with the respective movable contacts, a flat, punched sheet metal lever having a forked lower end freely slidable onto said block for positive driving of the latter by the former, a. pin upon which said lever is pivotally supported, a top plate having bearings formed integrally therewith to prevent downward displacement of said pin, a support plate rigidly attached to said top plate and overlying said pin to prevent upward displacement of the latter, said lever being manually operable to effect tilting oi said movable contacts jointly in one direction, and means comprising a coiled torsion spring respectively engaged with said support plate and said lever to effect automatic operation of the latter and tilting of said movable contacts in the reverse direction upon manual release of said lever.

13, In a multi-pole switch adapted for control of alternating current circuits, in combination, a recessed insulating base adapted to be produced by a straight-line molding operation, a plurality of sets of stationary and movable ccntacts located within said recess, the walls of said recess having barriers formed integraliy therewith to provide substantially separate arcing compartments for the respective sets of contacts, means for tiltably supporting said movable contacts, means for effecting 'tilting movement thereof into and out of engagement with the stationary contacts respectively associated therewith, said last mentioned means comprising a molded insulating block having a plurality of spring-pressed plungers associated therewith for continuous engagement with the respective movable contacts, a at, punched sheet metal lever having a forked lower end freely slidable onto said block for positive driving of the latter by the former, a pin upon which said lever is pivotally supported, a top plate having bearings formed integrally therewith to prevent downward displacement of said pin, a support plate rigidly attached to said top plate and overlying said pin to prevent upward displacement of the latter, said lever being manually operable to ef-.

fect tilting of said movable contacts jointly in one direction, means comprising a coiled torsion spring respectively engaged with said support plate and said lever to effect automatic operation of the latter and tilting of said movable contacts in the reverse direction upon manual release of said lever, said spring comprising a pair of substantially parallel arms, said arms havingstraight end portions interposed between and accommodated by said top and support plates, said arms also having coiled portions wound inwardly toward each other in a like direction and respectively surrounding said pin, said spring also having a substantially U-shaped portion connecting said arms, said lever having a notch in the side thereof opposite to said straight end portions of the spring, and said U-shaped portion of the spring being normally engaged with a predetermined degree of pressure against the lower wall of said notch.

' ALVIN W. KRIEGER. 

